Headscratchers / Phineas and Ferb The Movie: Candace Against the Universe

• When the gang meets up Dr. Doofenshmirtz at Doofenshmirtz Evil Incorporated, they of course didn't recognize him because their memories about him and his memories about them were wiped out at the end of Phineas and Ferb The Movie: Across the 2nd Dimension, but why Buford didn't recognize Doof if he had already meet him in the episode "Bully Bromance Breakup"? That episode took place after the movie.
• Speaking about Across the 2nd Dimension, why Major Monogram doesn't recall the events of the first movie while talking to Perry? He should have know that this isn't the first time Perry nearly blows up his cover...
• It's me or why the space looks so different in the movie than in the original show? In the original show, the space looked all black but here the space is depicted as more blue. That said, why the gang didn't even bring space suits with them? They really had luck that they were able to breathe on Feebla-Oot...
  • Animation updates for the first part. For the second, they were flying on Doof's rocket and the man isn't exactly known for thinking things through.
• How is possible that Super Super Big Doctor didn't realize that her plan would not serve in the long run? She could abduct as many humans she could, but they would eventually die (either by old age or due diseases) and, assuming she and her troops aren't immortal, once all humans went extinct because they would not be able to conceive offspring due their catatonic-like state, then Mama would have no more humans to produce carbon dioxide and her spores would wear off.
  • Simple-she doesn't know how humans work. It took Candace literally telling her that all humans breath Carbon Dioxide for her to know, so it's possible she doesn't know how humans reproduce either.
• When Dr. Doofenshmirtz uses his Chicken-Replace-inator to replace a dragon from Feebla-Oot, he then finds that he, Vanessa, Perry and Vlorkel can't leave Feebla-Oot because the nearest chicken is there and Vanessa doesn't let him kill it. What would have happened if Doof shot at the chicken and then shot at themselves before the chicken could reappear? Maybe both them and chicken would have returned to Earth in the process?
• If Mama aided Super Super Big Doctor on her plans, why she devoured her upon inhaling too much carbon dioxide?
• Why the crew bothered to give Jeremy and Stacy more important roles in the film? When they meet up, the impression is that they will join the fight against Super Super Big Doctor, but instead they drive away and meet up with Candace and the others.